Simultaneous Distillation Extraction Research Articles

Assessment of greenness for solid phase microextraction techniques of sample preparation for flavors by AGREE Prep & SPMS tools

Assessing the greenness of sample preparation techniques is essential due to the use of various solvents, chemicals, reagents, sorbents, pH adjustments, and energetic inputs. Solid-Phase Microextraction (SPME) is preferred over traditional flavor extraction methods such as Simultaneous Distillation Extraction (SDE) and Solvent-Assisted Flavor Evaporation (SAFE) because of its sensitivity, efficiency, speed, versatility, and economy. SPME fibers coated with stationary phases can extract volatile and semi-volatile flavor compounds from food samples, which are then desorbed and analyzed by Gas Chromatography-Mass Spectrometry (GC–MS). This article provides an assessment of the greenness of 50 SPME techniques for flavor analysis using the AGREE Prep and Sample Preparation Metric of Sustainability (SPMS) tools. This evaluation offers valuable insights into the environmental impact and sustainability of SPME as sample preparation techniques for flavour analysis. As per AGREE Prep, method 34 was found to be environmental friendly with score of 0.66, attributed to safe solvents, minimized waste, high sample throughput, and low energy consumption where as method 7 with SPMS scores of 7.05 is more sustainable due to miniaturization, fewer steps, and low energy use.

Comparative study of volatile compounds of cold-pressed oils extracted from three different oilseeds after gamma irradiation.

To investigate the effect of gamma irradiation on the volatile compounds of edible oils. Three types of oilseeds, including peanut, sesame, and flaxseed, were subjected to 8 kGy gamma irradiation, followed by cold pressing to extract their oils. The volatile compounds of the oils were isolated by simultaneous distillation extraction and analyzed by gas chromatography-mass spectrometry. A total of 91 volatile compounds were identified, which can be grouped into eight categories: hydrocarbons, aldehydes, ketones, alcohols, acids, esters, furans, and benzene derivatives. Irradiation treatment resulted in a significant increase in the levels of hydrocarbons, aldehydes, and ketones in all oil samples (p<0.05), with the greatest increase observed in hydrocarbons (4-14 times). In contrast, changes in alcohols, acids, esters, furans, and benzene derivatives were related to oilseed type. The increased hydrocarbons mainly originated from the degradation of palmitic, stearic, oleic, and linoleic acids. The irradiation resistance of the three oilseeds varied considerably, in the order: flaxseed>sesame>peanut. Based on the odor activity value, 11 key aroma compounds were selected, and (E)-2-decenal (tallow, oily, and orange), 1-octanol (soapy and oily), and 1-nonanol (floral and soapy) were only detected in the irradiated samples. Principal component analysis revealed that the oil samples of the three oilseeds could be well classified based on their key aroma compounds, and that the irradiation treatment had no remarkable effect on their intrinsic aroma.

Evaluation of High Vacuum Flavor Extraction Device as a Novel Technique for the Extraction of Volatile Compounds

In this study, a high vacuum flavor extraction (HVE) device was developed to address the limitations of traditional extraction methods, such as extended extraction times and artifact generation during high-temperature processes. Firstly, the repeatability and precision of the HVE method were evaluated through quantitative analysis of twelve volatile odor compounds across seven replicate extractions using gas chromatography–flame ionization detection (GC-FID). The results showed that the HVE system achieved a mean relative standard deviation (RSD) of 11.60 ± 1.79% and a recovery rate of 90.55 ± 4.56%, demonstrating its precision and reproducibility. Secondly, the performance of HVE was compared with solvent-assisted flavor evaporation (SAFE) and simultaneous distillation–extraction (SDE) for extracting flavor compounds from fried tilapia mince. The results indicated that HVE was more effective, particularly in extracting aldehydes and pyrazines, which are key contributors to the flavor profile. Finally, sensory evaluations supported these findings, showing that the odor profiles obtained through HVE were most similar to the original sample, with a similarity score of 72.55%, compared to 69.25% for SAFE and 60.29% for SDE. These findings suggest that HVE is a suitable method for the extraction and analysis of volatile compounds in complex food matrices such as fried tilapia mince.

Green synthesis of silver/silver oxide nanostructures using the Malva sylvestris extract prior to simultaneous distillation extraction: synthesis, phytochemical and biological analysis.

Nanotechnology and nanoscience are due to their numerous uses in medicine, engineering, and water pollution sensors and their expanding research fields. In this study, the essential oil, methanolic extract, and biosynthesized silver/silver oxide nanostructures (Ag/AgO NSs) using the aqueous extract of the plant were prepared. The phytochemical compounds of the extract and essential oil were analyzed using gas chromatography/mass spectrometry (GC/MS), respectively. The GC/MS technique identified 34 compounds in the essential oil of the plant with the major constituents including oleic acid (18.5%), palmitic acid (11.08%), phytone (6.64%), p-vinylguaiacol (6.4%), and phytol (4.23%). After the phytochemical identification, the total flavonoid and polyphenol contents of the extract was determined, too. Prodelphinidin B3 compound in the Malva sylvestris extract was analyzed and detected by high-performance liquid chromatography/ultraviolet detector (HPLC-UV), at a retention time of around 10 min. In addition, M. sylvestris extract was used for green synthesis of Ag/AgO NSs. The as-prepared NPs were characterized using X-ray diffraction (XRD), UV-visible absorption spectroscopy, scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (SEM/EDS), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), and Fourier transform infrared (FT-IR) analyses. Surface plasmon resonance (SPR) absorption at λmax 320 nm in the UV-vis spectra confirms the formation of Ag/AgO NSs. The crystalline structure of Ag/AgO NSs was confirmed by XRD analysis.The nanoparticles were found to have a small size, measuring 64.16 nm, 44.33 nm, and 50 nm using the Williamson-Hall, Scherrer, and SEM/EDS methods, respectively. Besides, that spherical shape of Ag NPs with good size distribution was observed in the SEM/EDS analysis. The small size, around 50 nm, and spherical shape of Ag/AgO NSs with good size distribution were observed in the SEM/EDS analysis. Besides, the antibacterial activity of the extract was evaluated against three pathogenic bacteria, by disk diffusion method. Significant antibacterial activity was observed for the prepared extracts of M. sylvestris against the bacteria (Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa), and the results were compared with the known antibiotics such as amoxicillin, cephalexin, erythromycin, and fluconazole.

Characterization of volatile profiles and markers prediction of eleven popular edible boletes using SDE-GC–MS and FT-NIR combined with chemometric analysis

Wild edible boletes mushrooms are regarded as a delicacy in many countries and regions due to their rich nutritional contents and strong aromatic compounds. This study aimed to identify 445 samples of 11 boletes species collected from Yunnan and Sichuan provinces through molecular analysis. Using simultaneous distillation–extraction (SDE) combined with gas chromatography-mass spectrometry (GC–MS), 97 volatile compounds were identified. Chemometric methods were then applied to analyze the heterogeneity of these volatile compounds among the different species. The results showed that, 22 and 21 volatile compounds were selected using variable importance in projection (VIP > 1) and relative odor activity values (ROAV > 0.1), respectively. Partial least squares discrimnatint analysis (PLS-DA) was then employed to develop pattern recognition models for 11 species, which demonstrated strong identification performance. Furthermore, correlation heat maps, volcano plots, and Fisher linear discriminant analysis identified five volatile organic compounds, including methyl (9E)-9-octadecenoate, 2, 6-dimethylpyrazine, 1-decen-3-one, furfural, and methional as markers for distinguishing 11 boletes species. Ultimately, the rapid content prediction models of partial least squares regression (PLSR) were established by combining Fourier Transform Near-Infrared Spectroscopy (FT-NIR) with the concentrations of these five marker compounds. These findings provide a methodological strategy for the effective species identification of wild edible mushrooms and the rapid prediction of their characteristic aroma compounds.

Volatile Flavor Compounds of Gamma Irradiated Melon (Cucumis melo L.) Seeds by Simultaneous Distillation Extraction and Gas Chromatography-Mass Spectrometry (GC-MS) Analysis

Gamma irradiation is one of the preservation techniques used to increase the shelf life of foods. The current study was aimed to determine the volatile flavor contents of melon (Cucumis melo L.) seeds and the impact of gamma radiation upon these compounds. The seeds were irradiated with gamma rays at 1, 5, 10, and 20 kGy doses. The volatile compounds were extracted by simultaneous distillation extraction (SDE), using n-pentane/diethyl ether (1:1, v/v) and determined by gas chromatography-mass spectrometry (GC-MS). A total of 70 volatile flavor compounds were identified in the control, with 2,3-butanediole (18.01%) and 1-hexanol (6.06%) as the major compounds. The number and percentage of the volatile compounds varied with the gamma irradiation doses. Twenty-eight volatile compounds were present in the non-irradiated and irradiated samples at different concentrations. Up to the recommended gamma irradiation dose of 10 kGy, the number of volatile flavor compounds generally increased. There were changes in both the number and percentages of the identified volatile flavor compounds following gamma irradiation of the Cucumis melo L seeds.

Comparative study of volatile components of soybean oil exposed to heating, ionizing and non-ionizing radiation

Heating and various radiation treatments have been widely used in the storage and processing of oilseeds. To compare the degradation effects of heating and different radiation treatments on oils, refined soybean oil was heated or radiated with γ-rays, microwave, ultraviolet and sunlight, while the oxidation indices, fatty acid composition and volatile constituents of the oils were analyzed. The results showed that all treatments had no significant effect on acid value and fatty acid composition, but oxidation indices (peroxide value, K232 and K268) were increased, especially for samples subjected to γ-rays and microwave radiation. The volatile components were analyzed using simultaneous distillation extraction combined with gas chromatography-mass spectrometry (SDE/GC-MS). A total of 82 volatile compounds were identified, including 18 alkanes, 19 alkenes, 30 aldehydes, 5 ketones, 4 alcohols, 2 furans and 4 benzenes. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed that there were significant differences in the volatile composition profiles of the oils after different treatments. The oils treated with gamma irradiation contained more alkenes, those treated with microwave radiation were rich in aldehydes, and those treated with sunlight radiation contained more alkanes.

Effect of storage time on aroma profiles of wuyi rock tea

Wuyi rock tea (WRT) is typically stored for weeks or months before consumption, and the roasted aroma changes into a floral aroma during the storage. However, little is known about the aroma change that occur during this period. The aroma in WRT during storage was extracted and identified using simultaneous distillation extraction coupled with gas chromatography mass spectrometry, in addition to calculating the odor activity value (OAV) and conducting aroma recombination experiments. The results revealed the emergence of floral aroma with increasing storage time. Alcohols, aldehydes, and aromatics were the main volatile types in WRT. According to partial least squares discriminant analysis, 20 volatiles were crucial variables contributing to the volatile differences in WRT with variations in storage time. The key volatiles causative for the overall aroma of WRT were determined based on their OAVs. In total, 25 volatiles with OAVs >1 were identified as aroma-active compounds. Notably, trans-β-ionone, 2-ethyl-3,5-dimethylpyrazine, linalool, octanal, nonanal, dehydro-β-ionone, and pentylfuran were substantial players in the overall aroma profile of WRT under storage. Based on the results of aroma combination experiments, the contribution of 18 volatiles with OAVs >2 to the overall aroma of WRT was confirmed. The findings augment our comprehension of aroma development in WRT throughout the storage.

Supercritical CO2 Extraction of Terpenoids from Indocalamus latifolius Leaves: Optimization, Purification, and Antioxidant Activity.

This study aimed to investigate the efficacy of supercritical CO2 (SC-CO2) extraction in enhancing the extraction rate, purity, and antioxidant activity of Indocalamus latifolius (Keng) McClure (Poaceae) leaf terpenoids (ILLTs). Crude extracts obtained from leaves were subjected to qualitative and quantitative analyses, revealing neophytadiene, phytol, β-sitosterol, β-amyrone, squalene, and friedelin as the primary terpenoid constituents, identified through gas chromatography-mass spectrometry (GC-MS). Compared with steam distillation extraction (SD), simultaneous distillation extraction (SDE), ultra-high pressure-assisted n-hexane extraction (UHPE-Hex), ultra-high pressure-assisted ethanol extraction (UHPE-EtOH), ultrasound-assisted n-hexane extraction (UE-Hex), and ultrasound-assisted ethanol extraction (UE-EtOH), SC-CO2 exhibited a superior ILLT extraction rate, purity, and antioxidant activity. Scanning electron microscopy (SEM) observations of the residues further revealed more severe damage to both the residues and their cell walls after SC-CO2 extraction. Under optimal parameters (4.5 h, 26 MPa, 39 °C, and 20% ethyl alcohol), the ILLT extraction rate with SC-CO2 reached 1.44 ± 0.12 mg/g, which was significantly higher than the rates obtained by the other six methods. The subsequent separation and purification using WelFlash C18-l, BUCHI-C18, and Sephadex LH-20 led to an increase in the purity of the six terpenoid components from 12.91% to 93.34%. Furthermore, the ILLTs demonstrated cytotoxicity against HepG2 cells with an IC50 value of 148.93 ± 9.93 μg/mL. Additionally, with increasing concentrations, the ILLTs exhibited an enhanced cellular antioxidant status, as evidenced by reductions in both reactive oxygen species (ROS) and malondialdehyde (MDA) levels.

Volatile Constituents of Some Myrtaceous Edible and Medicinal Fruits from the Brazilian Amazon.

Native and exotic fruits from the Amazon have varied characteristics, with aroma being a decisive factor in their acceptance for medicinal use as a nutraceutical supplement. This work aimed to analyze the chemical constituents of the volatile concentrates of some Myrtaceous fruit species sampled in the Brazilian Amazon. The fruit's pulps were subjected to simultaneous distillation-extraction, and gas chromatography-mass spectrometry was used to analyze their volatile chemical composition. In the volatile concentrate of Eugenia stipitata (Araçá-boi) α-pinene (17.5%), citronellyl butanoate (15.6%), and pogostol (13.5%) were identified as primary constituents; Eugenia uniflora (Ginja) concentrate comprised curzerene (30.5%), germacrone (15.4%), atractylone (13.1%), and (E)-β-ocimene (11.1%); in Myrciaria dubia (Camu-Camu), α-pinene (55.8%), (E)-β-ocimene (13.1%), and α-terpineol (10.0%) were present; in Psidium guajava (Goiaba) were (2E)-hexenal (21.7%), hexanal (15.4%), caryophylla-4(12),8(13)-dien-5-β-ol (10.5%), caryophyllene oxide (9.2%), and pogostol (8.3%); and in Psidium guineense (Araçá), limonene (25.2%), ethyl butanoate (12.1%), epi-β-bisabolol (9.8%), and α-pinene (9.2%) were the main constituents. The analyzed volatile concentrates of these fruit species presented a significant diversity of constituents with a predominance of functional groups, such as monoterpenes, sesquiterpenes, and fatty acid derivatives, originating from the plant's secondary metabolism and playing an important role in their nutritional and medicinal uses.

Characteristic odor of foxtail millet from different area with different sowing time based on gas chromatography-mass spectrometry

The odor of the foxtail millet is one of the most important indexes to evaluate the foxtail millet quality. Different sowing time results in different quality of the foxtail millet, and the volatiles can be used as fingerprint for distinguish them. The odor components of foxtail millets from spring sowing area and summer sowing area were investigated by means of gas chromatography-mass spectrometry (GC-MS) combined with simultaneous distillation extraction (SDE). A total of 53 volatile compounds were identified in all the samples containing 19 aldehydes, 4 alcohols, 7 ketones, 7 benzene derivatives, 12 hydrocarbons, 3 heterocycles and 1 acid. Aldehydes were the predominant odor components in foxtail millet. Compared with summer sowing area, there were abundant variety and high content of odor components in spring sowing area. Twenty-one volatiles were found to be odor-active compounds. The components with the highest OAVs in most sowing area were (E,E)-2,4-decadienal, (E)-2-nonenal, (E,E)-2,4-nonadienal and nonanal. Finally, 20 volatiles were screened out to distinguish the foxtail millet from spring-sowing area and summer-sowing area by multivariate statistical analysis. The results will be helpful to identify the foxtail millet from different sowing seasons and provide evidence that the spring-sowing foxtail millet shows more active odors.

Unraveling the contributing factors of stale odor in Longjing tea through a sensomics approach

Longjing tea is renowned for its fresh aroma and high value. However, during storage, the emergence of an off-flavor known as “stale odor” can significantly impact the flavor quality and economic benefits of Longjing tea. Yet, the specific volatiles responsible for this stale odor in Longjing tea remain unknown. In this study, Longjing tea samples with varying degrees of stale odor intensity were analyzed using simultaneous distillation extraction coupled with gas chromatography-mass spectrometry (SDE-GC–MS). Through odor activity value (OAV) and fractional omission testing, hexanoic acid and trans-2-nonenal were identified as the primary contributors to the stale odor. Moreover, the concentration of hexanoic acid was found to be valuable in predicting the intensity of the stale odor in Longjing tea. The oxidative degradation of linoleic acid was proved as the generation pathway of stale odor in Longjing tea. These findings provide essential theoretical principles for Longjing tea production and preservation.

Shale primary porosimetry based on 2D nuclear magnetic resonance of T1-T2

Porosity, a key parameter in assessing the physical properties of shale reservoirs and the reserves, is of great significance to the selection and evaluation of shale sweet spots. There are many methods at present to characterize shale porosity, most of which are aimed at post-core cleaning shale, such as those involving helium and saturated fluid (namely liquid-involved porosimetry). However, due to the low efficiency of shale core cleaning and the possible damage to pore structure during the core cleaning process, it's hard to guarantee the accuracy of porosity measurement. In this regard, we resort to the two-dimensional (2D) nuclear magnetic resonance (NMR) technology of T1-T2 in characterizing the primary shale porosity with samples taken from pressure coring in the 4th member of Shahejie Formation (Sha 4 Member) in well Fanxie 184 in the Jiyang Depression. Moreover, comparative experiments of shale porosity measurement by three methods, namely the simultaneous distillation extraction (SDE), helium and fluid measurement, are carried out simultaneously. The results show that the values obtained by SDE, gas and liquid measurement are similar, which are about 0.6 times of 2D NMR porosimetry. Core cleaning efficiency tends to seriously affect the results involving gas and liquid. In addition, the core cleaning treatment is bound to change the shale pore structure, and this is especially true in clay which tends to swell; consequently, porosity results are to be distorted by gas and liquid methods. It is thereby recommended to utilize the 2D NMR technology to characterize the primary total porosity of shale samples without core cleaning. The effective porosity of samples from pressure coring is determined by T2 cutoff value of around 0.3 ms.

Comparison of radiation-induced hydrocarbons formed in three irradiated oilseeds

To investigate the effect of fatty acid composition and irradiation dose on the radiation-induced hydrocarbons, three oilseeds (i.e., peanut, sesame and flaxseed) were selected and irradiated at 2, 4, 6 and 8 kGy. The radiation-induced hydrocarbons were extracted using simultaneous distillation extraction (SDE) and analyzed by gas chromatography-mass spectrometry (GC-MS). The most abundant fatty acid in peanut, sesame and flaxseed oils was oleic, linoleic and linolenic acid, respectively. Nine radiation-induced hydrocarbons including 1,3-bis(1,1-dimethylethyl)benzene and eight products from palmitic, stearic, oleic and linoleic acid were detected in all irradiated samples, even at 2 kGy. Compared to irradiated sesame and flaxseed, irradiated peanut had more radiation-induced hydrocarbons at the same dose. There was a visible difference in radiation-induced hydrocarbon composition among the three oilseeds. The radiolytic hydrocarbons derived from oleic and linoleic acid were predominant for peanut and sesame, while only oleic acid for flaxseed. The fatty acids in flaxseed were more readily cleaved at the alpha-carbon position compared to peanut and sesame. In addition, the concentrations of all detected radiation-induced hydrocarbons in three oilseeds increased linearly with irradiation dose (R2 = 0.957–0.993). The irradiated oilseeds from three different species could be distinguished by hierarchical cluster analysis based on their radiation-induced hydrocarbons.

Identification of aroma‐active components from cultivated agarwood ‘Qi‐Nan’ based on GC‐O‐MS combined with aroma extract dilution analysis

AbstractAgarwood ‘Qi‐Nan’ is commonly regarded as the highest quality agarwood, and has been highly valued for its fragrance. With the increasing amount of cultivated agarwood ‘Qi‐Nan’ in recent years, evaluation of the aroma compounds was drawn attention. Therefore, the volatile compounds in three cultivated ‘Qi‐Nan’ agarwood samples were extracted by simultaneous distillation‐extraction (SDE) and analysed by GC‐O‐MS, combined with aroma extract dilution analysis (AEDA). A total of 70 volatile compounds were identified from three samples, in which sesquiterpenes and aromatics were characterized as key aroma‐active components. Nine compounds were considered as common aroma‐active volatiles in these three essential oils according to their flavour dilution (FD) activity and relative flavour activity (RFA) value, and among them, dihydro‐β‐agarofuran and 4‐methoxy‐benzaldehyde were the most important aroma‐active compounds. Additionally, three ‘Qi‐Nan’ agarwood samples showed different aroma specificity. TD agarwood was characterized by sweet sandalwood odour due to the dominant aroma‐active compound of β‐Santalol. WS agarwood was distinguished by its woody odour because α‐kessyl acetate was its primary aroma. HQ agarwood was featured by woody, spicy and balsamic odour on account of its main aroma compounds of agarospirol and β‐elemene.

Protective effects of Pimpinella diversifolia DC. root essential oil against lipopolysaccharide/D-galactosamine-induced acute liver injury in mice through inhibiting inflammation and reducing oxidative stress

Acute liver injury (ALI) is a life-threatening syndrome with few therapeutic drugs are available. Excessive inflammatory response and imbalance of the antioxidant system are the hallmark of ALI. Therefore, anti-inflammatory and anti-oxidant treatment would be beneficial for ALI. Pimpinella diversifolia DC. is a perennial aromatic herb of the Umbelliferae family. The whole herb has been used as a medicine for thousands of years by the She ethnic minority of China, and is claimed to have beneficial health effects on liver disease. Its roots are rich in essential oil, but there are few reports on its pharmacological study. Therefore, the aim of the current work was to reveal the hepatoprotective effects of P. diversifolia root essential oil (PDREO). PDREO was prepared by a simultaneous distillation–extraction method and characterized by gas chromatography–mass spectroscopy (GC–MS). The potential application of PDREO in detoxification of liver injury was evaluated using a lipopolysaccharide (LPS)- and D-galactosamine (D-GalN)-induced acute liver injury mouse model. The results showed that the major constituents of PDREO were isodaucene (29.97%), 4-methoxy-2-(3-methyloxiranyl)-phenyl isobutyrate (19.53%), geijerene isomer (12.33%), and 2-methyl-4-methoxy-2-(3-methyl-2-oxiranyl) phenyl butyrate (6.88%). Isodaucene was identified in the essential oil of the Pimpinella species for the first time. Pre-treatment with PDREO (50 mg/kg) and (150 mg/kg) can effectively reduce the serum levels of alanine aminotransferase and aspartate aminotransferase, and dramatically alleviate liver edema, hemorrhage, hepatocyte apoptosis, and necrosis, which may be attributed to the significant anti-inflammatory activity (inhibiting the secretion of inflammatory cytokines and chemokines and reducing the infiltration of monocyte-derived macrophages and neutrophils) and the regulatory effects on oxidative stress (upregulating the expression of antioxidant enzymes such as GPX4, SOD1, and CAT) of PDREO. In addition, PDREO (150 mg/kg) can completely block the death of mice induced by LPS/D-GalN, while the survival rate of mice treated with the clinical first-line drug N-acetylcysteine (300 mg/kg) was only 10%. In light of the results obtained, PDREO is a promising natural detoxification agent, with potential applications in the food and pharmaceutical industries.

Comparative analysis of essential oils from two Satureja species; extraction methods, chemical composition, and antimicrobial activities

This study aimed to investigate the antibacterial and antifungal properties of the essential oils extracted from two medicinal plants, Satureja sahendica and Satureja spicigera. Three different methods, including Multi-walled carbon nanotubes (MWCNT) extraction, Clevenger hydrodistillation (Clevenger HD) extraction, and simultaneous distillation-extraction (SDE), were employed to isolate the volatile components of the two species, and then extraction efficiencies were compared. The composition of the essential oils was analyzed using gas chromatography-mass spectrometry (GC-MS). The results revealed that the two plant species contain a significant amount of oxygenated monoterpenes, while sesquiterpenes have a lower percentage. The main compounds of S. sahendica and S. spicigera essential were thymol (10.28–46.83%), carvacrol (7.81–36.88%), terpinolene (5.73–28.53%), ɣ-terpinene (14.76–16.27%), linalool (5.11–14.43%), p-cymene (8.23–12.33%), terpinen-4-0l (4.93–9.97%), germacerene (8.19–9.44%), α-pinene (5.22–8.41%), thymoquinane (4.49–7.65%), 1,8-cineole (4.82–6.83%), spathulenol (3.01–5.47%). To study the antibacterial and antifungal effects of the obtained essential oils, the micro broth dilution method was used on four bacterial species, including Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa, as well as the fungus Candida albicans. The results indicated that both species essential oils had a high activity against C. albicans, while P. aeruginosa was the most resistant bacteria. Furthermore, it was found that S. sahendica essential oil exhibited a greater antimicrobial effect than S. spicigera. This study provides valuable insights into the antibacterial and antifungal effects of essential oils extracted from S. Sahendica and S. Spicigera, which have potential applications in medicinal industry.

GC-O-MS Analysis of Aroma-Active Compounds of Chinese Almonds Obtained by Different Pretreatment Methods

Almonds (Prunus dulcis) are an ancient and commercially valuable crop from Asia. In this experiment, solid-phase microextraction (SPME), solvent-assisted flavor evaporation (SAFE), and simultaneous distillation extraction (SDE) were used to pretreat the almonds from China. The almond extract was then analyzed by aroma extract dilution analysis (AEDA) with gas chromatography-olfactory-mass spectrometer (GC-O-MS). SPME and SAFE were identified as the better extraction methods, and 52 aroma-active compounds of almonds, such as 1-nonanal, eugenol, and linalool, were identified based on odor activity values (OAVs). Aroma recombination and omission experiments showed that “sweet,” “fruity,” and “fatty” are the main aroma attributes of Chinese almonds, with a strong relationship with hexanal, heptaldehyde, 1-nonanal, etc. This experiment provides new insights into the sensory contribution of Chinese almond volatiles and helps Chinese almond producers characterize and market the aroma profile of Chinese almond varieties.

Chemical Composition, Antitumor Properties, and Mechanism of the Essential Oil from Plagiomnium acutum T. Kop.

Plagiomnium acutum T. Kop. (P. acutum) has been used as a traditional Chinese medicine for thousands of years to treat cancer but lacks evidence. The objective of this work was to reveal the chemical composition of P. acutum essential oil (PEO) and explore its potential antitumor activity and molecular mechanism. PEO was prepared by the simultaneous distillation-extraction method and characterized by gas chromatography/mass spectroscopy. CCK8 assay, flow cytometry, western blot, and immunofluorescence techniques were used to analyze the effects and mechanism of PEO against cancer cells. A total of 74 constituents of PEO were identified, with diterpenes (26.5%), sesquiterpenes (23.89%), and alcohols (21.81%) being the major constituents. Two terpenoids, selina-6-en-4-ol and dolabella-3,7-dien-18-ol, were detected in PEO for the first time. PEO showed significant cell growth inhibitory activity on HepG2 and A549 cells by blocking the G1 phase and inducing apoptosis, which may be attributed to its upregulation of p21Cip1 and p27Kip1 proteins and interference with mitochondrial membrane potential effect. Dolabella-3,7-dien-18-ol accounts for 25.5% of PEO and is one of the main active components of PEO, with IC50 values in HepG2 and A549 cells of (25.820 ± 0.216) µg/mL and (23.597 ± 1.207) μg/mL, respectively. These results confirmed the antitumor medicinal value of P. acutum and showed great application potential in the pharmaceutical industry.

Comparison of Odorants in Beef and Chicken Broth-Focus on Thiazoles and Thiazolines.

The shift in consumer landscape towards vegan, vegetarian and flexitarian diets has created an unprecedented challenge in creating meat aroma from plant-based alternatives. The search for potential vegan solutions has thus led to a renewed interest in authentic meat flavour profiles. To gain a better understanding of the qualitative odour differences between boiled beef and boiled chicken, aroma extracts were isolated using Likens-Nickerson simultaneous distillation-extraction (SDE), selected expressly because the in-situ heating of the sample facilitates the capture of aroma intermediates during the cooking process, thereby mimicking the cooking of meat in stocks and stews. The extracts were then analysed by Gas Chromatography-Mass Spectrometry (GC-MS) and GC-Olfactometry (GC-O). Most of the volatiles identified in this study were sulfur-containing compounds, such as sulfides, thiols, mercaptoaldehydes and mercaptoketones, which are derived from the Maillard reaction. Meanwhile, lipid oxidation results in the formation of unsaturated aldehydes, such as alkenals and alkadienals. Families of thiazoles and 3-thiazolines were found in the extracts. Two novel 3-thiazolines (5-ethyl-2,4-dimethyl-3-thiazoline and 2-ethyl-4,5-dimethyl-3-thiazoline) which may also contribute to the meaty aroma were identified in this work and synthesised from their respective aldehyde and mercaptoketone precursors.